Mechanical key code verification system

ABSTRACT

A mechanical key code verification system including a mechanical key and a lock apparatus into which the mechanical key is insertable. The mechanical key includes a key body and a key code pattern including a plurality of recessed portions and a plurality of non-recessed portions formed on the at least one plane of the key body, the key code pattern having line symmetry.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority fromprior Japanese Patent Application No. 2008-006056, filed on Jan. 15,2008, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

The present invention relates to a mechanical key code verificationsystem for use with a mechanical key having a key code pattern ofrecessed portions and non-recessed portions and including a lockapparatus that mechanically verifies the key code pattern.

In the prior art, various types of key systems are used to preventunauthorized use of articles, doors, and the like by a third person. Atypical key system uses a key that includes a grip and an elongated keyplate (also referred to as a key blade), which has an engraved key code.Insertion of the key plate into a cylinder of a lock apparatus alignsthe engraved key code with a plurality of disk tumblers (small steelpieces), which are biased by springs arranged in the cylinder. Rotationof the cylinder with the key is permitted when the key code of the keyplate matches a key shape formed by the disk tumblers. In such a case,the opening and closing of the lock apparatus is enabled. JapaneseUtility Model Registration No. 3090369 (patent document 1) and JapaneseLaid-Open Patent Publication No. 2004-76375 (patent document 2) describeexamples of a card key system using a card key. FIG. 10 illustrates acard key system 81. The card key system 81 includes a card key 82 and alock apparatus 86. The card key 82 has a key code pattern 83 including aplurality of holes 84 arranged in accordance with a key code of the cardkey 82.

FIG. 11 illustrates the lock apparatus 86 (also referred to as a fixedcomponent) in a state in which the card key 82 is not inserted therein.The lock apparatus 86 includes a supporting member 90 and a movablemember 88 supported by the supporting member 90. The movable member 88moves relative to the supporting member 90 when the card key 82 isinserted into the lock apparatus 86 to perform a key operation. Themovable member 88 and the supporting member 90 may be referred to as themovable side and fixed side, respectively. A plurality of pin tumblers87 are arranged so as to extend into the movable member 88 and thesupporting member 90. Each pin tumbler 87 includes a lock pin 89accommodated in the movable member 88 and a plunger pin 91 accommodatedin the supporting member 90. The plunger pin 91 is biased towards thelock pin 89 by a tumbler spring 92. The plurality of pin tumblers 87include first pin tumblers 87 a and second pin tumblers 87 b. In eachfirst pin tumbler 87 a, the plunger pin 91 is engaged with both of themovable member 88 and the supporting member 90 when the card key 82 isnot inserted into the lock apparatus 86. In each second pin tumbler 87b, a shear line between the lock pin 89 and the plunger pin 91 isaligned with a shear line between the movable member 88 and thesupporting member 90 when the card key 82 is not inserted into the lockapparatus 86.

As illustrated in FIG. 13, when the proper card key 82 is inserted intothe lock apparatus 86, the shear line between the lock pin 89 and theplunger pin 91 is aligned with the shear line between the movable member88 and the supporting member 90 in each of the pin tumblers 87 (firstpin tumblers 87 a and second pin tumblers 87 b). This permits movementof the movable member 88 with respect to the supporting member 90 sothat closing and opening of the lock apparatus 86 becomes possible.

As illustrated in FIG. 12, if the card key 82 inserted into the lockapparatus 86 is an improper key, the holes 84 of the card key 82 may bealigned with the first pin tumblers 87 a, and the second pin tumblers 87b may be aligned with non-hold portions 85 of the card key 82. In such afirst pin tumbler 87 a, the plunger pin 91 may be lowered by the amountthe distal end of the lock pin 89 is accommodated in the hole 84. Thus,the plunger pin 91 would be engaged with both of the movable member 88and the supporting member 90. In such a second pin tumbler 87 b, thedistal end of the lock pin 89 may be lifted by the non-hold portion 85of the card key 82. Thus, the lock pin 89 would be engaged with both ofthe movable member 88 and the supporting member 90. As a result, the pintumblers 87 prohibit movement of the movable member 88 relative to thesupporting member 90. Thus, the opening and closing of the lockapparatus 86 cannot be performed with an improper key.

-   [Patent Document 1] Japanese Utility Model Registration No. 3090369-   [Patent Document 2] Japanese Laid-Open Patent Publication No.    2004-76375

SUMMARY OF THE INVENTION

Due to the positions of the holes 84 in the key code pattern 83, inorder to verify the card key 82, the same side of the card key 82 mustalways be inserted first into the lock apparatus 86 with the card key 82facing the same direction. Otherwise, the card key 82 cannot be verifiedeven if it is a proper key, and the lock apparatus 86 thus cannot beopened or closed. More specifically, if the card key 82 is inserted intothe lock apparatus 86 in a reversed state or if the card key 82 isinserted sideways into the lock apparatus 86, the card key 82 cannot beverified.

The present invention reduces the number of times the direction in whicha card key is facing must be corrected when inserting the card key intoa lock apparatus.

One aspect of the present invention is a mechanical key codeverification system including a mechanical key and a lock apparatus intowhich the mechanical key is insertable. The mechanical key includes akey body having at least one plane. A key code pattern including aplurality of recessed portions and a plurality of non-recessed portionsis formed on the at least one plane of the key body. The key codepattern has line symmetry.

In one embodiment, the plurality of recessed portions and plurality ofnon-recessed portions in the key code pattern are arranged to besymmetric about a bisector of a right angle corner portion of themechanical key.

In one embodiment, the mechanical key code verification system is amechanical operation type key system arranged in a vehicle including anelectronic key system which verifies an electronic key code transmittedthrough wireless communication from an electronic key; and themechanical key is an emergency key for the electronic key system.

In one embodiment, the mechanical key is a card key.

In one embodiment, the plurality of recessed portions in the key codepattern are through holes.

In one embodiment, the lock apparatus includes a support member; and amovable member which is movable relative to the support member. Each ofthe tumblers is a pin tumbler including a first lock pin arranged in themovable member and a second lock pin arranged in the support member, inwhich mechanical verification of the key code pattern is establishedthereby enabling the movable member to be movable when a shear linebetween the first lock pins and the second lock pins of the plurality ofpin tumblers in the lock apparatus is aligned with a shear line betweenthe movable member and the support member in the lock apparatus.

In one embodiment, the mechanical key is a card key including aplurality of corner portions. The plurality of recessed portions of thekey code pattern are formed in the vicinity of single one of theplurality of corner portions. The vicinities of the other cornerportions are flat.

Other aspects and advantages of the present invention will becomeapparent from the following description, taken in conjunction with theaccompanying drawings, illustrating by way of example the principles ofthe invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention, together with objects and advantages thereof, may best beunderstood by reference to the following description of the presentlypreferred embodiments together with the accompanying drawings in which:

FIG. 1 is a block diagram of a key operation-free system;

FIG. 2 is a perspective view showing a lock apparatus and a card key fora mechanical operation type door lock system;

FIG. 3 is a plan view showing the positions of holes in the key codepattern of the card key and the layout of lock pins in the lockapparatus;

FIG. 4 is a cross-sectional view of the lock apparatus without the cardkey;

FIG. 5( a) is a cross-sectional view of the lock apparatus together witha proper card key, and FIGS. 5( b) and 5(c) are partial enlarged viewsof the lock apparatus together with an improper card key;

FIG. 6 is a cross-sectional view of the lock apparatus when opened bythe card key;

FIG. 7 is a cross-sectional view of the lock apparatus when closed bythe card key;

FIG. 8 is a diagram showing how the card key is used;

FIG. 9 is a diagram showing how to use a compact card key, which is cutout from a card key;

FIG. 10 is a plan view showing a lock apparatus before insertion of acard key in the prior art;

FIG. 11 is a cross-sectional view of the lock apparatus shown in FIG.10;

FIG. 12 is a cross-sectional view of the lock apparatus with a propercard key in the prior art; and

FIG. 13 is a cross-sectional view of the lock apparatus with an impropercard key in the prior art.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A preferred embodiment of a mechanical key code verification systemaccording to the present invention will now be discussed with referenceto FIGS. 1 to 9.

As illustrated in FIG. 1, a vehicle 1 incorporates a key operation-freesystem 2 that performs vehicle operations including the locking andunlocking of the doors and the starting and stopping of the enginewithout physically operating a vehicle key. The key operation-freesystem 2 uses a vehicle key (hereinafter referred to as portable device3) that transmits a unique ID code (key code) through wirelesscommunication. In the key operation-free system 2, the vehicle 1transmits a request signal Srq requesting the ID code. The portabledevice 3 returns an ID signal Sid including the ID code to the vehicle 1through narrow-band wireless communication in response to the requestsignal Srq. If the ID code of the portable device 3 matches an ID codeof the vehicle 1, the key operation-free system 2 enables the lockingand unlocking of the door and the starting and stopping of the engine.The key operation-free system 2 is one example of an electronic keysystem, and the portable device 3 is one example of an electronic key.

The key operation-free system 2 incorporates a smart entry system 4 thatlocks and unlocks the doors without any physical operation of thevehicle key. The smart entry system 4 will now be described. The vehicle1 includes a verification ECU 5 for verifying the ID code of theportable device 3 in the ID signal Sid received through narrow-bandwireless communication. The verification ECU 5 is connected to a vehicleexterior LF transmitter 6, a vehicle interior LF transmitter 7, and anRF receiver 8. The vehicle exterior LF transmitter 6 is arranged in eachdoor of the vehicle 1 to transmit a long frequency (LF band) signal outof the vehicle through wireless communication. The vehicle interior LFtransmitter 7 is arranged in the vehicle (e.g., in the floor etc.) totransmit a LF band signal within the vehicle through wirelesscommunication. The RF receiver 8 is arranged in the vehicle (e.g., inthe rearview mirror etc.) to receive an RF band signal through wirelesscommunication. The LF transmitters 6 and 7 transmit the request signalSrq through wireless communication. Specifically, the vehicle exteriorLF transmitter 6 forms a communication area (vehicle exteriorcommunication area) for the request signal Srq around the vehicle. Thevehicle interior LF transmitter 7 forms a communication area (vehicleinterior communication area) for the request signal Srq throughout theentire vehicle interior.

The verification ECU 5 is connected to a touch sensor 10 arranged, forexample, in a door handle 9 at the outer side of the vehicle (refer toFIG. 2). The touch sensor 10 detects a person touching the door handle 9when the door is locked to unlock the door. The verification ECU 5 isconnected to a lock button 11 arranged in, for example, the door handle9. The lock button 11 is pushed to lock the unlocked door. Theverification ECU 5 is connected to a door ECU 12, which controls thelocking and unlocking of the door though an in-vehicle LAN 13. The doorECU 12 locks or unlocks the door by driving a door lock motor 14 inaccordance with a command from the verification ECU 5.

The portable device 3 includes a communication control unit 15 forcontrolling wireless communication that is performed with the vehicle 1.The communication control unit 15 is connected to an LF reception unit16, which receives an LF band signal, and an RF transmission unit 17,which transmits an RF band signal in accordance with a command from thecommunication control unit 15. The LF reception unit 16 demodulates anLF band signal, which is received by an LF reception antenna 18 in an LFreceiver circuit 19, and provides the demodulated signal to thecommunication control unit 15 as received data. The RF transmission unit17 modulates transmission data provided from the communication controlunit 15 with an RF transmitter circuit 20, generates the ID signal Sidin the RF band with the unique ID code of the portable device 3, andtransmits the ID signal Sid from an RF transmission antenna 21.

When the vehicle 1 is in a parked state (engine stopped and doorslocked), the verification ECU 5 intermittently transmits the requestsignal Srq in the LF band to the vehicle exterior LF transmitter 6 andforms the vehicle exterior communication area around the vehicle. Whenthe portable device 3 enters the vehicle exterior communication area andreceives the request signal Srq with the LF reception unit 16, theportable device 3 transmits the ID signal Sid containing the ID coderegistered in a memory 22 to the RF transmission unit 17 as the RF bandwireless signal in response to the request signal Srq. In theverification ECU 5, the ID code of the portable device 3 contained inthe ID signal Sid and received by the RF receiver 8 is verified with theID code registered in a memory 23 (vehicle exterior verification). Whenthe vehicle exterior verification is completed, the verification ECU 5sets a vehicle exterior verification flag in the memory 23 over a fixedtime period and activates the touch sensor 10 in a standby state duringthat time period. When the activated touch sensor 10 detects that thevehicle exterior door handle has been touched, the door ECU 12 unlocksthe locked door by generating rotation with the door lock motor 14 inone direction.

In a state in which the vehicle 1 is not moving (engine stopped and doorunlocked), the verification ECU 5 transmits the request signal Srq tothe vehicle exterior LF transmitter 6 when detecting that the lockbutton 11 has been pushed. The verification ECU 5 performs the vehicleexterior verification on the ID signal Sid returned from the portabledevice 3 in response to the request signal Srq. The verification ECU 5provides a door lock request to the door ECU 12 when the vehicleexterior verification is completed. The door ECU 12 locks the unlockeddoor by generating rotation with the door lock motor 14 in the otherdirection in response to the door lock request.

The key operation-free system 2 includes a one-push engine start system24 enabling the starting and stopping of the engine by just operating avehicle switch. Physical operation of the vehicle key is not necessary.The one-push engine start system 24 will now be described. The vehicle 1includes an engine ECU 26 that executes ignition control and fuelinjection control on an engine 25, a gearshift ECU 27 that controlsautomatic transmission according to the operation of a gearshift lever,and a power supply ECU 28 that executes power supply management forin-vehicle electrical components. The ECUs 26 to 28 are connected tovarious ECUs including the verification ECU 5 through the in-vehicle LAN13.

An engine switch 29, which is operated when switching the power supplystate of the vehicle 1, is arranged near the driver's seat in thevehicle 1. The engine switch 29 is of a push-operation type and includesa switch portion 29 a that is pushed. The engine switch 29 is connectedto the power supply ECU 28 by a harness. The engine switch 29 has anengine starting and stopping operation function, which switches theengine 25 to a started state or a stopped state, and a power supplytransition operation function, which switches the power supply state ofthe vehicle 1 to an OFF state, an ACC ON state, or an IG ON state.

The power supply ECU 28 is connected to a vehicle speed sensor 30, whichdetects the travel speed of the vehicle 1, and a brake sensor 31, whichdetects the depression amount of the brake pedal. The power supply ECU28 recognizes the current traveling speed of the vehicle 1, which isbased on the vehicle speed information from the vehicle speed sensor 30,and determines depression of the brake pedal, which is based on thepedal depression amount information from the brake sensor 31. The powersupply ECU 28 is connected to an ACC relay 32, which is connected tovarious in-vehicle accessories, an IG relay 33, which is connected tothe engine ECU 26, and a starter relay 34, which is connected to astarter motor of the engine 25.

After the vehicle exterior verification is completed and the door isunlocked, the verification ECU 5 recognizes via a courtesy switch 35that the driver is entering the vehicle as the door opens. Theverification ECU 5 forms the vehicle interior communication area in theentire vehicle interior by transmitting the request signal Srq to thevehicle interior LF transmitter 7. When receiving the ID signal Sid inresponse from the portable device 3, which is located in the vehicleinterior communication area, with the RE receiver 8 (vehicle interiorverification), the verification ECU 5 verifies the ID code of theportable device 3 contained in the ID signal Sid with the ID coderegistered in the verification ECU 5. The verification ECU 5 sets avehicle interior verification completion flag in the memory 23 when thevehicle interior verification is completed.

When the driver pushes the engine switch 29 to switch the power supplystate of the vehicle 1, the power supply ECU 28 first checks theverification ECU 5 and determines whether the vehicle interiorverification has been completed. The power supply ECU 28 recognizes thatthe vehicle interior verification has been completed when notified bythe verification ECU 5 that the vehicle interior verification has beencompleted. When notified by the verification ECU 5 that the vehicleinterior verification ha not been satisfied, the power supply ECU 28instructs the verification ECU 5 to re-execute the vehicle interiorverification and re-check whether the vehicle interior verification hasbeen completed. The power supply ECU 28 continues to determine that thevehicle interior verification has not been completed even after theverification ECU 5 re-executes the vehicle interior verification unlessnotified by the verification ECU 5 that the vehicle interiorverification has been completed.

When the engine switch 29 is pushed in a state in which the brake pedalis depressed and the engine 25 is stopped, the power supply ECU 28activates the three relays 32 to 34 to start the engine 25 as long asthe vehicle interior verification is satisfied and then outputs anactivation signal to the engine ECU 26. When receiving the activationsignal, the engine ECU 26 checks the result of the vehicle interiorverification and then checks whether the verification ECU 5 and theengine ECU 26 are a proper pair by performing pairing through encryptioncommunication. If the two conditions are satisfied, the engine ECU 26initiates the ignition control and the fuel injection control to startthe engine 25. In a state in which the vehicle 1 stops moving (vehiclespeed “0”) and the engine switch 29 is pushed while the engine 25 isstill running, the power supply ECU 28 deactivates all of the threerelays 32 to 34 to stop the engine 25.

When the engine switch 29 is pushed but the brake pedal is not depressedin a situation in which the conditions are met of the engine 25 beingstopped, the vehicle interior verification being completed, and thegearshift lever being at the P range position, the power supply ECU 28sequentially shifts the power supply state in a manner of OFF state→ACCON state→IG ON state→OFF state whenever the engine switch 29 is pushed.In the above situation, the power supply state of the vehicle 1 isswitched from the OFF state to the ACC state when the engine switch 29is pushed once. From this state, the power supply state of the vehicle 1is switched to the IG ON state when the engine switch 29 is pushed againonce. From this state, the power supply state of the vehicle 1 returnsto the OFF state when the engine switch 29 is pushed again once.

A mechanical key code verification system, or mechanical operation typedoor lock system 36, illustrated in FIG. 2 will now be discussed. Themechanical operation type door lock system 36 is advantageous when aphysical key operation with a mechanical key becomes necessary to lockor unlock the doors. Since the smart entry system 4 (key operation-freesystem 2) is of an electrical type, a door cannot be locked or unlockedby the smart entry system 4 if the smart entry system 4 fails tofunction or if battery drainage occurs in the portable device 3. Themechanical operation type door lock system 36 is used to enable thelocking and unlocking of the doors under such situation.

The mechanical operation type door lock system 36 includes a lockapparatus 37, which is attached to an outer wall of the vehicle door(driver's seat door) 1 a, and a mechanical key 38. The mechanical key 38is inserted into the lock apparatus 37 and physically operated to open(unlock state) or close (lock state) the lock apparatus 37. In thepreferred embodiment, the mechanical key 38 is of a card type (flatplate-shape) and is thus also referred to as the card key 38. Themechanical operation type door lock system 36 may be referred to as acard key type door lock system. In a state in which the proper card key38 is inserted into a key hole 39 of the lock apparatus 37, the door islocked by moving the card key 38 from the initial position in a firstdirection (e.g., upward direction). In a state in which the proper cardkey 38 is inserted into the key hole 39 of the lock apparatus 37, thedoor is unlocked by moving the card key 38 from the initial position ina second direction (e.g., downward direction).

The mechanical operation type door lock system 36 is used during anemergency such as when the smart entry system 4 fails to function orwhen battery drainage occurs in the portable device 3. The card key 38is used as an emergency key during such an emergency. The card key 38 isflat and has a size similar to that of a typical credit card. Thus, thecard key 38 can be carried in a wallet, a card case, and the like in thesame manner as credit cards.

As illustrated in FIG. 2, a key body 40 (also referred to as caseportion) of the card key 38 has a key code pattern 41 defined on atleast one surface, such as a main surface, of the card key 38. One ormore recessed portions and one or more non-recessed portions are formedin the key code pattern 41. The array (pattern) of the holes 42 and thenon-hole portions 43 in the key code pattern 41 expresses the key codefor the card key 38 of the mechanical operation type door lock system36.

The recessed portions in the key code pattern 41 are holes 42 arrangedin the main surface of the key body 40. The non-recessed portions arenon-hole portions 43 defined in the main surface of the key body 40 atportions that do not include the holes 42. The key code pattern 41 isarranged near the distal end of the key body 40. Each hole 42 can be around through hole, such as a punched hole, extending through the keybody 40 but it does not necessary have to be round. The non-holeportions 43 may be projections. The holes 42 are one example of recessedportions. The non-hole portions 43 are one example of non-recessedportions.

Referring to FIG. 3, the key code pattern has line symmetry. Morespecifically, the holes 42 and non-hole portions 43 of the key codepattern 41 are arranged to be symmetric about a code pattern center lineLa, which extends across a corner portion 38 a of the card key 38 in oneexample, the card key 38 is rectangular and includes a first side 40 aand a second side 40 b. The first side 40 a has a dimensioncorresponding to the width of the card key 38. The second side 40 b hasa dimension corresponding to the length of the card key 38. The cornerportion 38 a is located between the first side 40 a and the second side40 b. The angle of the first side 40 a relative to the second side 40 bis, for example, ninety degrees. The code pattern center line La bisectsthe corner portion 38 a. In other words, the angle of the code patterncenter line La relative to the first side 40 a is, for example,forty-five degrees, and the angle of the code pattern center line Larelative to the second side 40 b is, for example, forty-five degrees.The corner portion 38 a is referred to as a right angle corner portion.The code pattern center line La is referred to as a bisector of theright angle corner portion.

Referring to FIGS. 4 to 7, the lock apparatus 37 includes a slider case44. The slider case 44 is the body portion of the lock apparatus 37 andis box-shaped. The key hole 39 (see FIG. 2) is formed in a side wall ofthe slider case 44. The slider case 44 is attached to the outer wall ofthe vehicle door 1 a. A slider 45 is accommodated in an accommodatingspace 44 a of the slider case 44 so as to be movable (linearly movable)relative to the slider case 44. The slider 45 is formed by a plate. Theslider 45 is movable in an R1 direction (FIG. 6) and an R2 direction(FIG. 7) in the accommodating space 44 a of the slider case 44. Theslider case 44 is one example of a support member, and the slider 45 isone example of a movable member. The slider case 44 may be referred toas a fixed side of the lock apparatus 37, and the slider 45 may bereferred to as a movable side of the lock apparatus 37.

The card key 38 when inserted into the key hole 39 is received in a keyslot 45 a, which is formed in the slider 45. The key slot 45 a hasdimensions that are slightly greater than the width and thickness of thecard key 38 to allow the insertion of different sizes of the card key38. Although not shown in the drawings, the slider 45 includes apositioning mechanism that positions the card key 38 at a keyverification position (pin alignment position) regardless of the size ofthe card key 38. The positioning mechanism may include a tab, which isformed on the side of the card key 38 that is first inserted into thelock apparatus 37, and a notch, which is formed in the inner portion ofthe slider 45 to be engageable with the tab of the card key 38.

As shown in FIGS. 4 to 7, pin tumblers 46 are arranged between theslider case 44 and the slider 45 to fix the slider 45 to the slider case44 and disable the locking and unlocking operation when the proper cardkey 38 is not used. The plurality of pin tumblers 46 each face one ofthe holes 42 or the non-hole portions 43 when the card key 38 isinserted into the lock apparatus 37. As shown in FIG. 3, the pintumblers 46 are arranged to be symmetric about a lock apparatus centerline Lb, which corresponds to the code pattern center line La. Thequantity of the pin tumblers 46 is the same as the total quantity of theholes 42 and non-hole portions 43 in the card key 38. For example, thereare nineteen pin tumblers 46 when there are eleven holes 42 and eightnon-hole portions 43. The pin tumblers 46 are one example of tumblers.

Each pin tumbler 46 includes a plunger pin 48 (second lock pin), whichis movably accommodated in a case side accommodation hole 47 formed inthe slider case 44, and a lock pin 50 (first lock pin), which is movablyaccommodated in a slider side accommodation hole 49 formed in the slider45. The pin tumbler 46 is constantly biased toward the slider 45 by atumbler spring 51 accommodated in the case side accommodation hole 47.The lock pin 50 is longer than the plunger pin 48. The lock pin 50 has adistal end formed by a round surface, for example, a semisphericalsurface. The tumbler spring 51 is one example of a biasing member.

The pin tumbler 46 includes one or more first pin tumblers 46 a, inwhich the lock pin 50 is short, and one or more second pin tumblers 46b, in which the lock pin 50 is long.

The first pin tumblers 46 a are located at positions corresponding tothe non-hole portions 43 of the proper card key 38 that is inserted intothe lock apparatus 37. When the card key 38 is not inserted into thelock apparatus 37 as illustrated in the state of FIG. 4 or when thefirst pin tumblers 46 a are forced into the holes 42 of an improper cardkey 38 as illustrated in the state of FIG. 5( b), the plunger pin 48 ofeach first pin tumbler 46 a engages both the slider case 44 and theslider 45 over a constant engagement length K (pin tumbler lockingstate) and restricts movement of the slider 45. When the proper card key38 is inserted into the lock apparatus 37 as illustrated in the state ofFIG. 5( a), the first pin tumblers 46 a are moved upward by an amountcorresponding to the engagement length K against the biasing force ofthe corresponding tumbler springs 51 by the non-hole portions 43 of thecard key 38. The shear line between the plunger pin 48 and the lock pin50 of each first pin tumbler 46 a (shear line between the two componentsof the plunger pin 48) becomes aligned with the shear line between theslider case 44 and the slider 45 (slide surface of the slider 45) (pintumbler unlocking state). The first pin tumblers 46 a in the pin tumblerunlocking state do not function to restrict movement of the slider 45.

The second pin tumblers 46 b are located at positions corresponding tothe holes 42 of the proper card key 38 that is inserted into the lockapparatus 37. When the card key 38 is not inserted into the lockapparatus 37 as illustrated in the state of FIG. 4 or when the secondpin tumblers 46 b are forced into the holes 42 of the proper card key 38as illustrated in FIG. 5( a), the shear line between the plunger pin 48and the lock pin 50 of each second pin tumbler 46 b is aligned with theshear line between the slider case 44 and the slider 45 (pin tumblerunlocking state) The second pin tumblers 46 b in the pin tumblerunlocking state do not function to restrict movement of the slider 45.When an improper key is inserted into the lock apparatus 37 asillustrated in the state of FIG. 5( c), the second pin tumblers 46 b areforced upward against the biasing force of the corresponding tumblersprings 51 by the non-hole portions 43. The second pin tumblers 46 bengage both the slider case 44 and the slider 45 (pin tumbler lockingstate) and restrict movement of the slider 45. The lift amount of eachsecond pin tumbler 46 b is the engagement length K of the lock pin 50 ineach second pin tumbler 46 b.

The slider 45 is connected to a dead bolt (not shown) or the door lockmember of the vehicle door 1 a by a transmission mechanism (not shown).The transmission mechanism transmits and converts the movement of theslider 45 to the mechanical opening and closing of the dead bolt.Referring to FIGS. 6 and 7, when the card key 38 is inserted into thelock apparatus 37, the slider 45 becomes movable in two directions froma neutral position. When the slider 45 is moved in one direction(direction of arrow R1 in FIG. 6) from the neutral position, thetransmission mechanism converts the movement of the slider 45 to aprojection operation of the dead bolt to unlock the vehicle door 1 a.When the slider 45 is moved in the other direction (direction of arrowR2 in FIG. 7) from the neutral position, the transmission mechanismconverts the movement to a retraction operation of the dead bolt to lockthe vehicle door 1 a.

The operation of the mechanical operation type door lock system 36 willnow be discussed.

When a driver tries to enter the vehicle 1, which is in a parked state(engine stopped, door locked state), if the key operation-free system 2fails to function or if battery drainage occurs in the portable device3, the doors cannot be unlocked with the key operation-free system 2. Insuch a case, the driver unlocks the vehicle door 1 a with the mechanicaloperation type door lock system 36. The driver may carry the card key 38of the mechanical operation type door lock system 36 in a wallet, a cardcase, or the like. The driver inserts the card key 38 into the key hole39 of the lock apparatus 37. The slider 45 is at the neutral positionwhen the card key 38 is inserted into the lock apparatus 37.

As illustrated in the state of FIG. 4, when the card key 38 is notinserted into the lock apparatus 37, the second pin tumblers 46 b are inthe pin tumbler unlocking state. However, the first pin tumblers 46 aare in the pin tumbler locking state. The first pin tumblers 46 arestrict movement of the slider 45 relative to the slider case 44. Thus,the slider 45 cannot be moved even when a person inserts his or herfingers into the key hole 39 of the lock apparatus 37 to forcibly movethe slider 45. In this manner, unauthorized opening and closing of thelock apparatus 37 is prevented.

When inserting the card key 38 into the key hole 39, the edge of thecard key 38 enters the gap below the distal ends of the pin tumblers 46and thereby lifts the pin tumbler 46. When the card key 38 is insertedinto the innermost portion of the key hole 39, if the card key 38 is aproper key, the non-hole portions 43 of the card key 38 are located atpositions corresponding to the first pin tumblers 46 a, and the holes 42of the card key 38 are located at positions corresponding to the secondpin tumblers 46 b, as shown in the state of FIG. 5( a).

If the card key 38 is a proper key, each first pin tumbler 46 a isforced upward by a distance corresponding to the sum of the platethickness of the card key 38 and the depth of the pin accommodationrecess 56 by the corresponding non-hole portion 43 of the card key 38against the biasing force of the tumbler spring 51. The shear linebetween the plunger pin 48 and the lock pin 50 of the first pin tumbler46 a is aligned with the shear line between the slider case 44 and theslider 45 (pin tumbler unlocking state). Each second pin tumbler 46 b isfitted into the associated hole 42 of the card key 38 and thus forcedtowards the slider 45 by the tumbler spring 51, and the shear linebetween the plunger pin 48 and the lock pin 50 of the second pin tumbler46 b is aligned with the shear line between the slider case 44 and theslider 45 (pin tumbler unlocking state).

The first pin tumblers 46 a and the second pin tumblers 46 b are both inthe pin tumbler unlocking state. Thus, the lock apparatus 37 is in aslider movable state in which the slider 45 is movable relative to theslider case 44. The slider 45 can be moved from the neutral positionwith the card key 38 when the lock apparatus 37 is in the slider movablestate. Therefore, if the proper key 38 is inserted into the lockapparatus 37 and moved in one direction (direction of arrow R1 in FIG.6) to move the slider 45 in that direction (as shown in the state ofFIG. 6) and open the lock apparatus 37, such movement is transmitted tothe dead bolt by the transmission mechanism. This retracts the dead boltfrom a projected state and unlocks the vehicle door 1 a.

The plunger pin 48 and the lock pin 50 of each of the pin tumblers 46must be facing toward each other to enable upward and downward movementsof the pin tumblers 46. That is, the card key 38 cannot be removed fromthe lock apparatus 37 unless the plunger pin 48 and the lock pin 50 ofeach pin tumbler 46 are facing each other. Therefore, after unlockingthe vehicle door 1 a, the driver returns the card key 38 to the initialposition by moving the slider 45 to the neutral position to remove thecard key 38 from the lock apparatus 37. The driver then pulls out thecard key 38 from the lock apparatus 37 and enters the vehicle whileholding the card key 38. The driver performs card key operations in thismanner to enter the vehicle.

When locking the vehicle door 1 a with the mechanical operation typedoor lock system 36, the proper card key 38 is inserted into the lockapparatus 37 in which the slider 45 is located at the neutral position.Then, the driver moves the card key 38 in the other direction (directionof arrow R2 of FIG. 7) to move the slider 45 in the other direction(state illustrated in FIG. 7). In this case, the movement of the slider45 is transmitted to the dead bolt by the transmission mechanism. Thisprojects the dead bolt from the retracted state to lock the vehicle door1 a. When removing the card key 38 from the lock apparatus 37 afterlocking the vehicle door 1 a, the driver returns the card key 38 to theinitial position by moving the slider 45 to the neutral position. Then,the driver pulls the card key 38 out from the lock apparatus 37 in thesame manner as when unlocking the vehicle door 1 a with the lockapparatus 37.

The operation of the mechanical operation type door lock system 36,especially, the card key 38 will now be discussed.

The card key 38 includes a widthwise direction (the direction of arrowZ1 in FIG. 8) and a lengthwise direction (the direction of arrow Z1 inFIG. 8). The key code pattern 41 is symmetric on opposite sides of thecode pattern center line La, which bisects the corner portion 38 a. Dueto the symmetry of the key code pattern 41, the card key 38 may beinserted into the lock apparatus 37 in two states. FIG. 8 shows thefirst insertion state and the second insertion state. In the firstinsertion state, the first side 40 a of the card key 38 is firstinserted into the lock apparatus 37. In the second insertion state, thesecond side 40 b of the card key 38 is first inserted into the lockapparatus 37. From the first insertion state, the card key 38 is rotatedby 90 degrees within the same plane and then obverted (turned upsidedown) to shift to the second insertion state. Therefore, the card key 38when in the first insertion state is rotated by 180 degrees about thecode pattern center line La to shift to the second insertion state.

For example, when the user takes out the card key 38 from a wallet orthe like and holds the card key 38 with the first side 40 a or thesecond side 40 b facing forward, the user does not have to correct thedirection in which the card key 38 is being held to open or close thelock apparatus 37. That is, the user just inserts the first side 40 a orsecond side 40 b first into the lock apparatus 37. This reduces thenumber of times the direction in which the card key 38 is facing must becorrected when inserting the card key 38 into the lock apparatus 37.

Further, since the key code pattern 41 is line-symmetric about the codepattern center line La, the card key 38 may be cut to reduce the size ofthe card key 38. FIG. 9 shows a normal or regular-size card key 52,which is identical to the card key 38 shown in FIGS. 2, 3, and 8. Theregular-size card key 52 includes a perforation Lx, which is parallel tothe first side 40 a. By cutting the regular-size 1 card key 52 along theperforation Lx, a compact card key 53, which includes the key codepattern 41 can be obtained. If the first side 40 a is facing forward, toinsert the second side 40 b first into the lock apparatus 37, thecompact card key 53 may be rotated by 90 degrees within the same planeand then obverted.

For example, a user who wishes to use the card key 38 with the regularsize does not cut the card key 38 and thus uses the regular-size cardkey 52. A user who wishes to reduce the size of the card key 38 cuts theregular-size card key 52 along the perforation Lx and uses the compactcard key 53, which includes the key code pattern 41. In this manner, thesize of the card key 38 may be changed in accordance with the user'spreference. Further, the regular-size card key 52 can easily be changedto the compact card key 53 just by performing a single cuttingoperation.

The preferred embodiment has the advantages described below.

(1) The key code pattern 41 of the card key 38 includes the holes 42 andthe non-hole portions 43, which are arranged to be symmetric about thecode pattern center line La that bisects the corner portion 38 a of thecard key 38. Thus, the card key 38 can be inserted into the lockapparatus 37 in a plurality of insertion states. This reduces the numberof times the direction in which the card key 38 is facing must becorrected when inserting the card key 38 into the lock apparatus 37.

(2) The key code pattern 41 of the card key 38 (regular-size card key52) is symmetric about the code pattern center line La, which bisectsthe right angle corner portion 38 a of the card key 38 (regular-sizecard key 52). Thus, the compact card key 53 can be obtained from theregular-size card key 52 by just cutting the regular-size card key 52once. The size of the card key may be changed in accordance with theuser's preference. This improves convenience. Further, the regular-sizecard key 52 can easily be cut.

(3) The compact card key 53 is smaller in size than the regular-sizecard key 52. Thus, the compact card key 53 may be accommodated in asmaller space. This is advantageous for an emergency key.

(4) The card key 38 functions as an emergency key for the keyoperation-free system 2, and an emergency mechanical key does not needto be accommodated in the portable device 3. The emergency mechanicalkey can thus be omitted from the portable device 3, and the portabledevice 3 can be further miniaturized by the omission of the emergencymechanical key.

(5) The lock apparatus 37 of the mechanical operation type door locksystem 36 is of a pin tumbler type that includes two types of pinmembers and is thus simple.

(6) The card key 38 is thin and card-shaped. Thus, the card key 38 maybe accommodated in a small space in a wallet or the like. Thus, the cardkey 38 may be easily carried.

(7) The card key 38 includes in the key code pattern 41 a key codeexpressed by the existence and non-existence of holes 42 formed in acard material (plate material). The holes 42 may be replaced withrecesses having closed bottoms when forming the key code in the card key38. However, such a card key 38 would have to be thicker to providesufficient depths for bottomed recess. Such a thick card key is notpreferable. The card key 38 of the preferred embodiment is thin sincethe holes 42 extend through the card key 38.

It should be apparent to those skilled in the art that the presentinvention may be embodied in many other specific forms without departingfrom the spirit or scope of the invention. Particularly, it should beunderstood that the present invention may be embodied in the followingforms.

As long as the key code pattern 41 of the card key 38 is line-symmetric,there is no need for the center line La to extend across the cornerportion 38 a of the card key 38 or be diagonal to the card key 38. Forexample, a line extending perpendicular to the first side 40 a or secondside 40 b of the card key 38 may be used as the center line La, with thekey code pattern 41 being symmetric about the center line La. As long asthe key code pattern 41 is symmetric, the center line La, to which thekey code pattern 41 would be symmetric, may extend in any direction.

The quantity of the holes 42, the quantity of the non-hole portions 43,the ratio between the holes 42 and the non-hole portions 43, and thetotal quantity of the holes 42 and non-hole portions 43 are not limitedin any manner and may be changed. Further, the hole distance and holediameter do not have to be set as fixed values.

The card key 38 does not have to be shaped like a credit card asdescribed above. For example, the card key 38 may be shaped so as toinclude a wireless communication mechanism (RFID tag) enablingidentification of an individual or electronic payment.

The shape of the holes 42 in the key code pattern 41 is not limited inany manner and does not have to be round. For example, the holes may beoblong, tetragonal, or triangular. Further, the holes 42 are not limitedto round holes having the same dimensions and may include small roundholes and large round holes. Alternatively, the holes 42 may includeround holes and holes having other shapes.

The mechanical key of the mechanical operation type door lock system 36is not limited to the card key 38, which is a very thin plate shapedidentically to a credit card, and may be a rather thick plate such as amemory card. Further, the mechanical key does not have to be tetragonal(rectangular) and may have any shape. For example, the mechanical keymay be round.

It is preferable that the holes 42 that form the key code pattern 41extend through the card key 38. However, recesses that do not extendthrough the card key 38 may be used in lieu of the holes 42.

The lock apparatus 37 is not limited to a structure for manually movingthe slider 45 with the card key 38. An electrical structure fordetecting the pin tumbler unlocking state of all the pin tumblers with asensor and moving the slider 45 with power from the motor and the likemay be adopted.

The lock apparatus 37 is not limited to a slide type in which themovable member (slider 45) linearly slides and may be a rotatable typein which the movable member is rotated by a key.

The lock apparatus 37 is not limited to a structure in which the slider45 moves in two directions from a neutral position to open or close thelock apparatus 37. For example, the lock apparatus 37 may have astructure in which the lock apparatus 37 switches between open andclosed states whenever the slider 45 is moved in the same direction fromthe neutral position.

The biasing member for biasing each pin tumbler 46 is not limited to aspring and may be a rubber material.

The lock apparatus 37 is not limited to a pin tumbler-type including thepin member, and may be a disk tumbler-type in which the tumbler memberis plate-shaped.

The activation of the relays 32 to 34 is not limited to electricalmanagement by the power supply ECU 28 and may be a mechanical type inwhich the relays are switched between activated and deactivated statesby the physical operation of a key.

The electronic key system is not limited to a key operation-free system2 in which the locking and unlocking of the door and the starting andstopping of the engine are automatically permitted or executed as longas the driver is carrying the proper portable device 3. A wireless keysystem in which various operation buttons are formed in the electronickey may be used in which an operation request command and key code aretransmitted to the vehicle 1 through wireless communication when such abutton is pushed.

The engine starting and stopping system of the vehicle 1 is not limitedto a one-push engine start system 24 and may be a mechanical operationengine starting and stopping system in which the mechanical key 38 isinserted into the engine starting and stopping key cylinder and turnedto start or stop the engine. In this case, the card key 38 may be usedto switch electrical power supplies of the vehicle 1.

The mechanical operation key system using the card key 38 is notnecessarily limited to emergency use with the smart entry system 4 andmay be used during an emergency of the one-push engine start system 24.The mechanical operation key system using the card key 38 of thepreferred embodiment merely needs to be adopted in at least one of thesmart entry system 4 or the one-push engine start system 24.

The key operation-free system 2 may be an immobilizer system thatperforms wireless ID verification with a communication tag componentincorporated in the portable device 3. In the immobilizer system, theportable device 3 is held near a transponder key coil, which is arrangedin a vehicle. This causes the coil to transmit drive radio waves thatactivate a transponder in the portable device. Then, the activatedtransponder sends a transponder code signal to the vehicle 1, and thevehicle 1 performs ID verification (immobilizer verification) using acode that is included in the transponder code signal. In this case,in-vehicle verification, which must be established to start the engine,does not have to be performed after the key operation-free system 2establishes ID verification (in-vehicle verification) and may beperformed when any one of the key operation-free system 2 and theimmobilizer system establishes ID verification.

The mechanical operation type door lock system 36 is not limited tovehicles, and may be used in various components for opening and closingcomponents such as the door of a house and the like.

In the illustrated example, the holes 42 of the key code pattern 41 arearranged in the vicinity of only one of the corner portions of the cardkey 38 (e.g., the right angle corner portion 38 a) and the other cornerportions are flat and do not include such structures in theirvicinities. However, projections or holes that are not part of the keycode pattern 41 may be formed in the vicinity of the other cornerportions.

In the illustrated example, the holes 42 and non-hole portions 43 of thekey code pattern 41 are arranged at intersections of the first inclinedlines, which are inclined to the first side 40 a of the card key 38, andthe second inclined lines, which are inclined to the second side 40 band the center line La. However, the holes 42 and non-hole portions 43of the key code pattern 41 may be arranged at intersections of aplurality of lines parallel to the first side 40 a of the card key 38and a plurality of lines parallel to the second side 40 b of the cardkey 38.

The present examples and embodiments are to be considered asillustrative and not restrictive, and the invention is not to be limitedto the details given herein, but may be modified within the scope andequivalence of the appended claims.

1. A mechanical key code verification system comprising: a mechanicalkey; and a lock apparatus into which the mechanical key is insertable;the mechanical key including: a key body having at least one plane; anda key code pattern including a plurality of recessed portions and aplurality of non-recessed portions formed on the at least one plane ofthe key body, the key code pattern having line symmetry, wherein theplurality of recessed portions and the plurality of non-recessedportions in the key code pattern are arranged to be symmetric about abisector of a right angle corner portion of the mechanical key.
 2. Themechanical key code verification system according to claim 1, wherein:the mechanical key code verification system is a mechanical operationtype key system arranged in a vehicle including an electronic key systemwhich verifies an electronic key code transmitted through wirelesscommunication from an electronic key; and the mechanical key is anemergency key for the electronic key system.
 3. The mechanical key codeverification system according to claim 1, wherein the mechanical key isa card key.
 4. The mechanical key code verification system according toclaim 3, wherein the plurality of recessed portions in the key codepattern are through holes.
 5. The mechanical key code verificationsystem according to claim 1, wherein: the lock apparatus includes: asupport member; a movable member which is movable relative to thesupport member; and a plurality of pin tumblers, each including a firstlock pin arranged in the movable member and a second lock pin arrangedin the support member, in which mechanical verification of the key codepattern is established thereby enabling the movable member to be movablewhen a shear line between the first lock pins and the second lock pinsof the plurality of pin tumblers in the lock apparatus is aligned with ashear line between the movable member and the support member in the lockapparatus.
 6. The mechanical key code verification system according toclaim 1, wherein: the mechanical key is a card key including a pluralityof corner portions; the plurality of recessed portions of the key codepattern are formed in the vicinity of a single one of the plurality ofcorner portions; and the vicinities of the other corner portions areflat.